Antioxidant and cytoprotective effects of sequentially extracted Terminalia prunioides pods

Oxidative stress has been linked to a wide array of health-debilitating diseases. To alleviate oxidative stress, antioxidants especially of plant origin are desired due to their potency and low toxicity. The current study, therefore, evaluated the antioxidant properties and cytoprotective effects of Terminalia prunioides pods. Hexane, chloroform, ethyl acetate and methanol extracts from Terminalia prunioides pods were evaluated for flavonoid and total phenol contents. Their effects on 2, 2-diphenyl-1-picryl hydrazyl (DPPH), 2,2’-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid (ABTS), Superoxide dismutase (SOD), Catalase (CAT), reduced glutathione (GSH) and Ferric reducing antioxidant power (FRAP) were evaluated. The extracts were also tested for their cytoprotective effects on HeLa cells against H₂O₂, using 4-[−3(4-Iodophenyl)-2-(4-nitro-phenyl)-2 H-5-tetrazolio]-1,3-benzene sulfonate (WST-1) assay. The methanol extract possessed 67.8 ± 10.4 mg QE/g and 113.2 ± 7.6 mg GAE/g of total flavonoid (TFC) and total phenolic contents (TPC) respectively. Methanol extracts from Terminalia prunioides pods recorded IC₅₀ values of 0.06 mg/mL, 0.07 mg/mL, and 0.24 mg/mL for DPPH, FRAP and ABTS assays respectively. Catalase (CAT), reduced glutathione (GSH) and Superoxide Dismutase (SOD) activities were significantly increased (p < 0.05) in HeLa cells treated with Terminalia prunioides pods extracts. The current study’'s findings indicate the high antioxidant activity of Terminalia prunioides pods extracts and cytoprotection of HeLa cells from H₂O₂ induced cell death.